Method and apparatus for classifying and sorting closure caps

ABSTRACT

Jar caps of the vacuum-indicating, flip panel type are classified and sorted according to panel flexure characteristics. Two different positions of each panel are induced by successively establishing high- and low-pressure differentials across the panel. In each case the panel position is compared to the norm therefor. A memory device information retrieval element is correspondingly conditioned to signalize either deviance or freedom therefrom in respect of both induced positions. The memory device is then investigated and the cap is classified accordingly. Apparatus is provided for automatically classifying and sorting caps. The caps are serially fed to a carrier which traverses a series of cams. The cams actuate switches controlling vacuum, sensing, and memory device components. The memory device retrieval element controls an ejector according to the mode prevailing. The ejector discharges caps from the carrier at different locations according to whether a particular cap is rejected or accepted with respect to both comparisons.

United States Patent [72] Inventor Roger Warren Melton Waukegan, Ill. [21] Appl. No. 51,432 [22] Filed July 1, 1970 [45] Patented Jan. 11, 1972 [73] Assignee Continental Can Company, Inc.

New York, N.Y.

[54] METHOD AND APPARATUS FOR CLASSIFYING AND SORTING CLOSURE CAPS 16 Claims, 6 Drawing Figs.

52 U.S.Cl 209/80,

73/37 51 1m.c| B07c5/00 so FieldofSearch 209/79,s0;

Primary Examiner-Allen N. Knowles Assistant E.\'aminer-Gene A. Church Attorneys-George E. Szekely, Joseph E. Kerwin and William A. Dittmann ABSTRACT: Jar caps of the vacuum-indicating, flip panel type are classified and sorted according to panel flexure characteristics. Two different positions of each panel are induced by successively establishing highand low-pressure differentials across the panel. in each case the panel position is compared to the norm therefor. A memory device information retrieval element is correspondingly conditioned to signalize either deviance or freedom therefrom in respect of both induced positions. The memory device is then investigated and the cap is classified accordingly. Apparatus is provided for automatically classifying and sorting caps. The caps are serially fed to a carrier which traverses a series of cams. The cams actuate switches controlling vacuum, sensing, and memory device components. The memory device retrieval element controls an ejector according to the mode prevailing. The ejector discharges caps from the carrier at different locations according to whether a particular cap is rejected or accepted with respect to both comparisons.

PATENTED JAM 1 I972 5 74 SHEET 1 0F 3 HIGH VACUUM LOW VACUUM CA F D P N E FLIP oowm FLIP-UP :DEVIANCE IJEVIANCE: I SIGNAL SIGNAL I l I MEMORY J STORAGE ACCEPTABLE CAPS DISCHARGE I E ACCEPT CLASSIFY REJECT R E J ECTS DISCHARGE I N VENTUR ROGER W MELTON BY W ATT' Y PATENTEDJAH1 1 I972 Mn 3 UF 3 TO ELECTRIC D-FJ :ACCE

INVENTOR ROGER W MHTON m M ATT' Y.

METHOD AND APPARATUS FOR CLASSIFYING AND SORTING CLOSURE CAPS BACKGROUND OF THE INVENTION I. Field of the Invention This invention relates to classifying and sorting vacuum jar caps, more particularly those caps having vacuum-indicating, flexible top panels, with respect to flexural characteristics of the panels. The nature and uses of such caps are described in US. Pat. No. 3,l60,302, issued to George F. Chaplin, Dec. 8, 1964. A top panel of the type there described and here of interest is hereafter referred to as flip panel.

2. The Prior Art Flip panels are designed for substantial flexural response to pressure differential. As usually formed, a flip panel is essentially a domed disc spring. When the vacuum-sealed, capped jar is exposed to atmosphere, the resultant pressure differential includes downward snap action flexure of the panel, generally termed flip-down. Typically, the panel is then perceptibly dished. The jars being generally virtually full of product, and the flip panel having a strong upward bias due to its spring characteristic, a small volume of air infiltration will reduce the pressure difierential sufficiently to induce snap back of the panel near to its normal dome position. Thus, the ultimate purchaser can readily tell at sight or by touch whether or not the jar remains properly vacuum-sealed.

After vacuum-packing jars having caps with flip panels, it is usual to probe each panel for flip-down. If a panel does not exhibit the prescribed dish, the jar is unacceptable as apparently not having a desired vacuum. A probe error signal actuates an automatic ejector, removing the corresponding jar from the line.

The foregoing inspection system for checking packed jars is generally satisfactory. However, the system does not account for possible abnormal flexural response of the panel. Should a particular panel be overly flexible, an improperly sealed jar may be passed, or the panel may take a permanent set. An abnormally stiff panel failing to flip down properly would indicate defective sealing, when in fact the jar may have been properly sealed. Thus, the procedure does not account for deviant flexural characteristics of the panel. In particular, the procedure provides no check of recovery or flip-up characteristics. The packer therefore must rely entirely upon the cap supplier to insure that every cap panel has appropriate flexural characteristics.

Quality control procedures for quantity manufacture of caps with flip panels involve sophisticated, exacting inspection techniques. I-leretofore, these procedures have proved to be quite costly, at least partly for want of a reliable high-production method and apparatus providing economical direct inspection for flexural characteristics of the panels.

SUMMARY OF THE INVENTION The major object of this invention is to provide a method and apparatus for automatically classifying and sorting jar caps of the flip panel type, the system being adaptable for I percent direct inspection of the panels with respect to their critical flexural characteristics.

According to the method of this invention, two different pressure differentials are successively imposed on the flip panel, correspondingly including successive flexures of the panel to two different positions. The pressure differentials are preferably established by drawing vacuum interiorly of the cap, inducing flip-down flexure of the panel, then relieving the vacuum to reduce the differential, inducing flexure of the panel to flip-up position.

Each panel position is sensed and compared to a prescribed position or norm corresponding to the imposed pressure differential. By virtue of imposing vacuum in high-low sequence, the determination with respect to flip-up position reflects the fiexural recovery characteristics of the panel, under conditions simulating those in service. If either induced position is found to exhibit deviance, a signal is thereupon sent to a memory device, and stored therein in a signalizing mode. Upon one subsequent investigation, the memory device signalizes exhibition of deviance in respect of either of the two induced positions, so that the corresponding cap can thereupon be classified as accepted or rejected in respect of both positions according to the result of the one investigation of the memory device.

The foregoing method is well adapted to rapid sorting of caps fed serially along a production line. Apparatus for this purpose includes a table with a series of cams thereon and a revolvable carrier having an arm which transverses the cams as the carrier revolves. The arm carries a series of control switches actuated in stages by corresponding cams so as to appropriately sequence the operations of vacuum imposition, sensing and signalling, and memory investigation. The arm also carries a cap holder arranged for sealing the interior of the cap and thereby defining a chamber with the panel as a wall thereof. The chamber is then in communication with a vacuum system through regulators. An airblast ejector nozzle is positioned on the arm opposite the cap in the holder.

The memory device has an information retrieval element comprising first and second branches constituting alternative signalizing modes. A flip-flop element is preset to establish one mode, but throws to the other mode upon receiving a deviance signal from the panel sensing system. Each branch is connected to a separate one of two control switches, which are connected in parallel to an ejector control valve. The switches and their corresponding cams are so arranged that the ejector control is first coupled momentarily to the deviance signalizing branch for investigation thereof. If that mode prevails, the resultant signal actuates the cap ejector, blowing the cap from the holder. The ejector control is then coupled to the normal-mode branch. Normal memory mode prevails at this second investigation stage, if the deviance mode was not previously evoked. A cap present at this stage is an acceptable one and is ejected on the second memory investigation. In a final stage a cam actuates a memory reset control switch, which restores normal mode, if the deviance mode has been previously evoked. The apparatus is thus readied for the next cap of the series.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional outline view of a jar cap of the vacuumindicating type, showing the positions of the flip panel under different degrees of vacuum, with a schematic showing of a sensing and signalling system according to this invention;

FIG. 2 is a flow chart illustrating the method of this invention;

FIG. 3 is a perspective outline view of a turret-type classifying and sorting apparatus for practicing the method illustrated by FIG. 2;

FIG. 4 is a end elevational view of the cap holder and probe head;

FIG. 5 is a diagram of the vacuum system for the apparatus of FIG. 3; and

FIG. 6 is a diagram of the signal and control system for the apparatus of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring first to FIG. 1, jar cap 10 has a flip panel 11 which is normally domed, as indicated by the solid line. The physical properties and normal curvature of panel 11 are so selected that when the cap is applied to the jar and sealed under vacuum of prescribed normal value, the resultant pressure differential across panel 11 induces flexure thereof to the flipdown position indicated by the broken line (11),. Should the vacuum in the jar fall significantly, as by infiltration, the reduction of pressure differential, plus bias of the panel toward normal dome position, causes panel 11 to snap back to a flip-up position, as indicated at (11):, close to as-formed position.

The flexural characteristics of the cap panel are sensitive to small manufacturing variations. It is therefore desirable that each panel be inspected directly with respect to those characteristics before the cap is placed on a jar. According to this invention, each cap is checked for both flip-up and flip-down positions, under pressure differential conditions which simulate conditions in service.

The preferred inspection and classification method is outlined as follows:

I. Feed cap to receiving station.

2. Apply high vacuum.

3. Sense panel; signal memory, if deviance sensed.

4. Apply low vacuum.

5. Sense panel, signal memory, if deviance sensed.

6. Vent vacuum.

7. Investigate memory, classify cap accordingly as rejected or accepted.

For production sorting, caps are fed serially. After classification, each cap is delivered to one of two collection points, according to its classification.

The flow chart of FIG. 2 illustrates procedure for production classifying and sorting. The block at the upper left indicates cap infeed, from which point caps move in series to the high vacuum or flip-down determination stage. At this stage the position of the panel is sensed and compared to a prescribed norm. If the position is determined to be deviant, a signal is transmitted to the memory device for storage. Then the cap is subjected to the low vacuum or flip-up condition. The panel position is now sensed and compared to the norm for low vacuum condition. If the position is found deviant, the same corresponding signal is transmitted to memory, as at the first determination stage As hereafter described, the memory device is adapted for alternative information retrieval modes. One branch is preset as a normal mode, which prevails until a signal is transmitted from the sensing system. The other branch is conditioned as a deviant mode on signal from the sensing system at either determination stage. In the classification stage, the deviantmode retrieval branch is investigated. If that mode has been invoked, the cap panel is defective and the cap is discharged to rejects. Then the normal retrieval branch is investigated. If the cap is present at this stage, the retrieval element is in normal mode, indicating an acceptable cap. That cap is then discharged at the corresponding collection point.

Referring now to FIG. 3, the preferred classifying and sorting apparatus is a rotary machine having a revolvable arm 12 and a table 13. The single-arm arrangement shown is suitable for inspecting one cap per revolution of the arm. A multiarm turret, with control system commutator, otherwise similar to the apparatus shown, can be employed for online sorting at even higher production rates, without increasing the rotative speed.

Arm 12 is rotatable around vertical shaft 14 and is driven by any suitable means (not shown). Arm 12 carries successive caps around and over the table 13, which supports a number of cams for initiating and timing the various operations as each cap traverses the cam table 13. For this purpose, limit switches 15 are suspended from arm 12 and coact with the corresponding cams on the face of table 13. The cams are suitable positioned to oppose the corresponding switches, to actuate them at appropriate times and to hold them closed for desired duration in each case as arm 12 traverses table 13. The operation stages are designated by numbers I to IX, substantially in time sequence, although certain operations are simultaneous or overlap, as hereafter described. The stage numbers are shown on the face of the table, lead lines representing the lines of initiation for respective operations and the starting points of corresponding cam elements. The master control switch 30 and memory device 31 are housed in box 35.

Caps are fed serially into holder 16, on cap per arm revolution. The caps may be fed manually, but in high-production operation the caps are preferably fed from a conveyor timed in synchronism with the rotat on of arm 12, as understood by those skilled in production line operations involving automatic machinery.

Holder 16 supports a sensor assembly including probe positioning cylinder 17. The holder 16 and the associated parts are best seen in FIG. 4. The function of this portion of the apparatus is to position and seal the cap for imposition of vacuum and for thereafter sensing the position of the panel I]. A set of guides 18 centers and retains cap 10 on pad 19. Pad 19 is adapted to seal against lip 20. For this purpose, the pad is preferably made of a resilient material, such as rubber. Alternatively, the upper face 21 may comprise a seal facing of rubber or plastic. Pad 19 also serves as a vacuum manifold, being provided with a passage 22 in communication with the chamber 23, which is defined by the cap and face 21. Flip panel 11 constitutes the upper wall of chamber 23. A gauge 60 is provided for reading the vacuum in chamber 23.

The probe and sensor system here shown is of the contact type. A proximitytype sensor can be used if desired. Air

cylinder 17 is clamped to holder frame 30 with piston rod 24 extending downward toward pad 19. Rod 24 is clamped to one end of sensor head bracket 28, whose opposite end is provided with a clip 26 slidable on leg 75 of frame 30, so that bracket 28 reciprocates vertically with rod 24. The adjustable stop screw 74 at the tip of rod 24 limits downward stroke of the rod and bracket 28 by striking the upper face of pad 19. A two-position microswitch 25 is carried on bracket 28 with the switch plunger 27 opposing the center of flip panel 11. Stop screw 74 is adjusted so as to establish a lowermost probe position of plunger 27 with its point just clear of flip panel 11 at its uppermost normal flip-down position. In this probe position of plunger 27, switch 25 is open.

The signal system is best seen in the diagram of FIG. 1. This system is designed to emit a signal if (a) panel position (1 I is upward of the norm for that position or (b) position (11), is downward of its norm. The two positions are sensed in sequence indicated. Switch plunger 27 carries a contactor 34. With plunger 24 at its lowermost position, spaced from panel 11, contactor 34 is clear of switch contact (25),. If panel 11 flips down less than the prescribed amount for high vacuum, the panel 11 at its unacceptably higher position raises plunger 24 so that contactor 34 closes to contact (25), for signalling the memory device 31, as hereafter described.

Switch 25 here shown is a slide type, contactor 34 sliding along line (25) between downward and upward limit contact points (25), and (25) respectively. It will be understood that any of various well-known two-position switch arrangements can be used, with suitable motion multiplier, if desired, according to the throw range involved.

After sensing panel position at high vacuum, low vacuum is imposed. The induced upward snap or flip of panel 11 toward position (11 raises plunger 27, carrying contact 34 upward with it against the bias of switch spring 29. If the panel position (ll) is below normal, contactor 34 is closed to contact (25) on line (25 in circuit with memory device 31. But if the panel snaps up to normal, higher position, contactor 34 is thrown to open position of switch 25. Thus, the closed switch positions at (25), and (25 correspond to deviance with respect to flip-down and flip-up panel positions respectively. Switch 25 is preferably of the adjustable throw type to accommodate variations in high-low vacuum range, or variations in down-up range of panels in different cap sizes or styles.

Referring again to FIG. 3, a control actuation and operation of the various components and systems will now be described in association with the description of the operations in several stages, reference being also had to FIGS. 5 and 6 for diagrams of vacuum and electric control systems respectively.

In automatic operation, arm 12 revolves continuously at constant speed. In stage I, just subsequent to infeed of a cap, the innermost switch 37 is tripped by cam 36, actuating highvacuum regulating valve 51. Valve 51 is connected to a suitable vacuum system (not shown) and communicates with chamber 23 through line 61 and passage 22 (FIG. 4), thereby drawing prescribed high vacuum in chamber 23 and so clamping and sealing cap on pad 19. Drawing the vacuum also induces top panel flip-down toward the normal high vacuum position (ll) (FIG. 1).

immediately thereafter, at stage II, cam 38 closes switch 39, which is in circuit with solenoid valve 32. Valve 32 is in communication with an air pressure line (not shown) and with the probe actuating cylinder 17, through conduit 33. Upon opening of valve 32, pressure admitted to cylinder 17 moves rod 24 down in its predetermined stroke, whereupon bracket 28 and switch 25 assume the sensing position shown in FIG. 4.

At stage III button cam 42 closes switch 43 momentarily, coupling sensor switch 25 to memory device 31. If switch 25 is in its closed position, as previously described, the cap is unacceptable, with respect to its flip-down position. In such case a signal is impressed on memory device 31, coupling thereof to switch 25 conditioning the information retrieval element accordingly. Details of the memory device, its conditioning and investigation are described hereafter.

At stage IV cam 44 closes switch 45, thereby positioning low-vacuum regulating valve 63 to partial vent condition, relieving the vacuum in chamber 23 to a low value, corresponding to flip-up position (11) (FIG. 1) of panel 11. The residual vacuum is sufficient to hold the cap sealed on pad 19. The panel flips up, raising plunger 27 to an upper position and holding it there, sensing the panel position at low vacuum. Thereupon, button cam 46 momentarily closes switch 47, again coupling the sensor switch 25 with memory device 31. If the position sensed is below normal a signal is impressed on memory device 31, as in the case of position deviance at stage III, above described. The signal conditions the memory device retrieval element in its mode characteristic of deviance, if not already so conditioned at stage III.

At stage V, switches 37 and 45 leave cams 36 and 44, respectively, releasing the vacuum regulation valves 51 and 63 to their vented, no-vacuum positions. The cap is thus freed, except for frictional restraint imposed by the guides 18 (FIG. 4). The restraint precludes cap throwout by centrifugal action of the arm 12.

At stage VI cam 38 releases switch 39, and thereby valve 32, releasing rod 27 for retraction to its up position, carrying bracket 28 upward from panel 11.

At stage VII, button cam 48 momentarily closes switch 49. As best seen in FIG. 6, switch 49 is in circuit with the deviance mode retrieval branch 69 of memory device 31 and with ejec- 't0r control solenoid valve 64. If a signal appears, the signal is impressed on valve 64, opening it and admitting pressure air to nozzle 50, which blows cap 10 from holder 16. Caps thus ejected can be collected in a hopper of by a conveyor.

At stage VIII button cam 54 momentarily closes switch 55, which is connected to the normal or acceptable" mode branch 68 of the memory device retrieval element (FIG. 6) and to ejector control valve 64. If there is a cap in the holder when now presented, that cap is an acceptable one, not having been ejected in stage VII. The signal transmitted through the closed normal mode retrieval circuit now effects ejection of the good cap to discharge at stage VIII, in the same manner as above described for ejecting a reject at stage VII. The acceptable caps can be captured in boxes, hoppers, or on a conveyor for further processing or shipment.

At stage IX, cam 56 momentarily closes switch 57, which is in circuit to a retrieval mode reset control in memory device 31. The reset circuit operates to restore the memory device to normal mode, if the memory device has been previously conditioned in deviance characteristic mode, at stage II of stage IV.

FIG. 6 diagrams the control system, signal circuits and the memory device 31. Controls shown are primarily electric. However, fluidic or electronic controls, or other such control analogs may be employed, as well known in the signal and control arts. In the system shown, the memory device 31 is of the electromechanical flip-flop type, with its retrieval element comprising two branches 68 and 69. Reversing switch 66 is under the influence of reversing coil 67. Switch 66 is normally closed to retrieval branch 68, in circuit with limit switch 55, constituting the normal retrieval mode circuit. If sensor switch 25 is closed at either sensing stage, as above described, the momentary closing of either corresponding signal circuit switch 43 or 47 pulses coil 67, throwing switch 66 into circuit with limit switch 49, and closing the circuit to the deviant mode retrieval branch 69. Closing of switch 49, investigating the retrieval element as to establishment of its deviance characteristic mode, then actuates the ejector control valve 64 by virtue of the signal passing through branch 69.

With switch 66 closed to normal mode retrieval branch 68, closing of switch 25 actuates valve 64 for ejection of an acceptable cap, as above described. If switch 66 has been closed to branch 69, due to sensing of a deviant panel position at either sensing stage, switch 66 is reset to normal by momentarily closing reset switch 57, which puts coil 67 on line through switch 49 at its normal rest position, closed in circuit with tieline 71. The resultant pulse on coil 67 throws switch 66 to it normal closed position in circuit with normal mode branch 68.

The remainder of the diagram in FIG. 6 is self-explanatory, showing the air and vacuum control circuitry and switches, identified in the foregoing description of the operations involved, as arranged for controlling head actuation and the vacuum system (FIG. 5).

The method and apparatus above described provide for automatically classifying and sorting caps with respect to two flip panel positions, at a high production rate. Some modifications have been noted in course of describing the preferred embodiment. Other modifications within the spirit and scope of the invention will be apparent upon reading the foregoing description.

What is claimed is:

1. In a method of classifying a closure cap having a flexible top panel, according to flexural characteristics thereof, there being norms for flexural positions of the panel corresponding to pressure differentials imposed thereon, the steps of,

a. successively imposing two different pressure differentials on the panel, thereby inducing flexure of the pane toward corresponding positions;

b. comparing each position induced to the corresponding norm therefor, thereby determining in respect of each position whether the panel exhibits deviance;

c. pursuant to finding deviance in respect to either induced position, generating a signal and transmitting the signal to a memory device adapted to store the signal in one signalizing mode; and thereafter,

d. investigating the memory device in respect of the one mode, thereby at once signalizing whether the panel exhibits deviance in respect of either induced position.

2. The invention defined in claim 1, including imposing pressure differentials having the same algebraic sign, in highlow sequence, thereby inducing flexural recovery of the panel from its first position toward its second position.

3. The method defined in claim 2, including imposing the higher pressure differential by drawing vacuum interiorly of the cap, then decreasing the vacuum to impose the lower pressure difi'erential.

4. The invention defined in claim 1, wherein the memory device is adapted for conditioning in a second signalizing mode alternative to the one mode and for separate investigation in respect of each mode, including preconditioning the retrieval element in the second mode; and separately investigating the memory device in respect of each mode, thereby positively signalizing exhibition of deviance or freedom therefrom in respect of both positions, according to which ever mode prevails.

5. The invention defined in claim 4, including feeding a series of the caps along a course, performing in turn the like steps in respect of each cap while in course, and diverting each cap from the course at one or another location according to the mode signalized, thereby sorting the caps in course into two classes according to deviance or freedom therefrom in respect of both positions.

6. In a method of classifying a closure cap having a resiliently flexible top panel, according to flexural charac teristics thereof, there being norms for acceptable different flexural positions of the panel corresponding to different pressure differentials imposed thereon, the steps of,

a. imposing a pressure differential on the panel, thereby inducing flexure of the panel toward a first position;

b. comparing the first position induced to the corresponding norm;

c. decreasing the pressure differential, thereby inducing flexural recovery of the panel from the first position toward a second position,

d. comparing the second position induced to the corresponding norm; and

e. classifying the cap as to acceptability with regard to both comparisons, thereby accounting for flexural recovery characteristics of the panel in classifying the cap.

7. Apparatus for classifying a closure cap having a flexible top panel, according to flexural characteristics thereof relative to norms for positions of said panel induced by pressure differentials thereon, said apparatus comprising:

means for successively imposing two different pressure differentials on said panel, so as to correspondingly induce flexure of said panel toward first and second positions thereof;

means for sensing deviance in respect of each said induced position in turn; memory means having a storage system including an information retrieval element adapted for conditioning thereof in a predetermined mode and for signalizing said mode upon investigation of said storage system;

signalling means responsive to said sensing means upon sensing thereby of either said deviance for sending a signal to said memory means so as to store said signal and thereby condition said element in said mode; means for investigating said storage system so as to signalize said mode when said mode prevails, thereby signalizing whether said panel exhibits deviance in respect of either said induced position; and means adapted to control others of said means for cyclic operation thereof in predetermined sequence.

8. The invention defined in claim 7, including movable carrier means having a member carrying a holder for said cap, said member being arranged for movement with said cap along a path, said control means being arranged for effecting said operations in timed relation to said movement.

9. The invention defined in claim 8, including regulating means for first effecting imposition of the higher of said pressure differentials having the same algebraic sign, whereby to account for flexural recovery characteristics of said panel upon sensing of said second position.

10. The invention defined in claim 8, including ejector means responsive to said element when conditioned in said mode for ejecting said cap from said carrier means; and means arranged and timed for coupling said ejector means to said memory means so as to investigate said element in respect of said mode during said movement subsequent to said sensing, whereby to automatically eject said cap from said carrier means pursuant to said panel exhibiting said deviance.

ll. The invention defined in claim 10, said memory means being arranged for presetting of said element in a normal mode alternative to said first-named mode and for distinguishably signalizing the prevailing one of said modes upon investigation of said element; said ejector means being responsive to said element in either of said modes, said coupling means being arranged so as to effect investigation in respect of first one then the other of said modes, whereby to eject said cap at one or another stage of said movement, according to whether or not said panel exhibits either of said deviances.

12. The invention defined in claim 8, said holder including means for sealing said cap so as to define a chamber with said panel constituting a wall thereof; conduit means arranged for communication between said chamber and means for drawing vacuum therein; and means foncontrollably re ulating said vacuum so as to establish said pressure di erentials in predetermined sequence.

13. The invention defined in claim 8, including a table, said carrier including a member arranged for traversing said table in course of said movement, said traverse member carrying elements of said sequencing control means arranged in series and having actuation means opposing said table, cam means being arranged on said table for controlling said actuation means so as to effect said predetermined operation sequence in course of said movement.

14. The invention defined in claim 13, wherein said carrier means is revolvable, said control elements being generally arranged in radial series, said cam means comprising cam elements arranged on said table in radial and circumferential series so as to efiect one cycle of said operations within one revolution of said carrier means.

15. The invention defined in claim 12, including timing control means for said regulating means arranged to effect relief of said vacuum subsequent to said sensing operations, said holder having means thereon for restraining said cap with predetermined force independent of vacuum against ejection of said cap from said holder.

16. The invention defined in claim 8, said sensing means including a probe head movable between retracted and sensing positions relative to said cap in said holder, there being head actuation means operable to move said head between said positions thereof, and control means associated with said head actuation means for moving said head in timed relation to sensing operations of said sensing means relative to said cap. 

1. In a method of classifying a closure cap having a flexible top panel, according to flexural characteristics thereof, there being norms for flexural positions of the panel corresponding to pressure differentials imposed thereon, the steps of, a. successively imposing two different pressure differentials on the panel, thereby inducing flexure of the pane toward corresponding positions; b. comparing each position induced to the corresponding norm therefor, thereby determining in respect of each position whether the panel exhibits deviance; c. pursuant to finding deviance in respect to either induced position, generating a signal and transmitting the signal to a memory device adapted to store the signal in one signalizing mode; and thereafter, d. investigating the memory device in respect of the one mode, thereby at once signalizing whether the panel exhibits deviance in respect of either induced position.
 2. The invention defined in claim 1, including imposing pressure differentials having the same algebraic sign, in high-low sequence, thereby inducing flexural recovery of the panel from its first position toward its second position.
 3. The method defined in claim 2, including imposing the higher pressure differential by drawing vacuum interiorly of the cap, then decreasing the vacuum to impose the lower pressure differential.
 4. The invention defined in claim 1, wherein the memory device is adapted for conditioning in a second signalizing mode alternative to the one mode and for separate investigation in respect of each mode, including preconditioning the retrieval element in the second mode; and separately investigating the memory device in respect of each mode, thereby positively signalizing exhibition of deviance or freedom therefrom in respect of both positions, according to which ever mode prevails.
 5. The invention defined in claim 4, including feeding a series of the caps along a course, performing in turn the like steps in respect of each cap while in course, and diverting each cap from the course at one or another location according to the mode signalized, thereby sorting the caps in course into two classes according to deviance or freedom therefrom in respect of both positions.
 6. In a method of classifying a closure cap having a resiliently flexible top panel, according to flexural characteristics thereof, there being norms for acceptable different flexural positions of the panel corresponding to different pressure differentials imposed thereon, the steps of, a. imposing a pressure differential on the panel, thereby inducing flexure of the panel toward a first position; b. comparing the first position induced to the corresponding norm; c. decreasing the pressure differential, thereby inducing flexural recovery of the panel from the first position toward a second position; d. comparing the second position induced to the corresponding norm; and e. classifying the cap as to acceptability with regard to both comparisons, thereby accounting for flexural recovery characteristics of the panel in classifying the cap.
 7. Apparatus for classifying a closure cap having a flexible top panel, according to flexural characteristics thereof relative to norms for positions of said panel induced by pressure differentials thereon, said apparatus comprising: means for successively imposing two different pressure differentials on said panel, so as to correspondingly induce flexure of said panel toward first and second positions thereof; means for sensing deviance in respect of each said induced position in turn; memory means having a storage system iNcluding an information retrieval element adapted for conditioning thereof in a predetermined mode and for signalizing said mode upon investigation of said storage system; signalling means responsive to said sensing means upon sensing thereby of either said deviance for sending a signal to said memory means so as to store said signal and thereby condition said element in said mode; means for investigating said storage system so as to signalize said mode when said mode prevails, thereby signalizing whether said panel exhibits deviance in respect of either said induced position; and means adapted to control others of said means for cyclic operation thereof in predetermined sequence.
 8. The invention defined in claim 7, including movable carrier means having a member carrying a holder for said cap, said member being arranged for movement with said cap along a path, said control means being arranged for effecting said operations in timed relation to said movement.
 9. The invention defined in claim 8, including regulating means for first effecting imposition of the higher of said pressure differentials having the same algebraic sign, whereby to account for flexural recovery characteristics of said panel upon sensing of said second position.
 10. The invention defined in claim 8, including ejector means responsive to said element when conditioned in said mode for ejecting said cap from said carrier means; and means arranged and timed for coupling said ejector means to said memory means so as to investigate said element in respect of said mode during said movement subsequent to said sensing, whereby to automatically eject said cap from said carrier means pursuant to said panel exhibiting said deviance.
 11. The invention defined in claim 10, said memory means being arranged for presetting of said element in a normal mode alternative to said first-named mode and for distinguishably signalizing the prevailing one of said modes upon investigation of said element; said ejector means being responsive to said element in either of said modes, said coupling means being arranged so as to effect investigation in respect of first one then the other of said modes, whereby to eject said cap at one or another stage of said movement, according to whether or not said panel exhibits either of said deviances.
 12. The invention defined in claim 8, said holder including means for sealing said cap so as to define a chamber with said panel constituting a wall thereof; conduit means arranged for communication between said chamber and means for drawing vacuum therein; and means for controllably regulating said vacuum so as to establish said pressure differentials in predetermined sequence.
 13. The invention defined in claim 8, including a table, said carrier including a member arranged for traversing said table in course of said movement, said traverse member carrying elements of said sequencing control means arranged in series and having actuation means opposing said table, cam means being arranged on said table for controlling said actuation means so as to effect said predetermined operation sequence in course of said movement.
 14. The invention defined in claim 13, wherein said carrier means is revolvable, said control elements being generally arranged in radial series, said cam means comprising cam elements arranged on said table in radial and circumferential series so as to effect one cycle of said operations within one revolution of said carrier means.
 15. The invention defined in claim 12, including timing control means for said regulating means arranged to effect relief of said vacuum subsequent to said sensing operations, said holder having means thereon for restraining said cap with predetermined force independent of vacuum against ejection of said cap from said holder.
 16. The invention defined in claim 8, said sensing means including a probe head movable between retracted and sensing positions relative to said cap in said holder, there being head actuation means operable to move said head between said positions thereof, and control means associated with said head actuation means for moving said head in timed relation to sensing operations of said sensing means relative to said cap. 